Abstract
BACKGROUND: In veterinary medicine, particularly concerning dogs and cats, there is limited data regarding vancomycin-resistant Enterococcus (VRE). However, multidrug-resistant Enterococcus is frequently identified, raising concerns about the potential for spreading these resistant microorganisms to humans due to their zoonotic nature. This study aimed to identify VRE colonizing animals admitted to a veterinary hospital and to determine the presence of the major resistance genes responsible for vancomycin resistance. RESULTS: Enterococcus was found to carry the vanA gene in 52.54% of cases, the vanB gene in 23.73%, the vanC gene in 20.34%, and the vanE gene in 3.39%. The antimicrobials with the lowest resistance were chloramphenicol (5.08%) and ampicillin (6.78%). In contrast, the highest resistance was observed with enrofloxacin (79.66%), rifampicin (67.80%), and ciprofloxacin (61.02%). Seven Enterococcus isolates showed resistance to vancomycin as well as high-level aminoglycoside resistance (HLAR). CONCLUSION: A total of 46 animals were found to be colonized by VRE, of which 16 were healthy. The vanA gene was the most commonly isolated (52.54%), followed by vanB (23.73%), vanC (20.34%), and vanE (3.39%). This represents the first report of the vanE gene being identified in a dog in Brazil. Among the 59 Enterococcus isolates, 84.75% (n = 50) were found to be multidrug resistant. The colonization of VRE and Enterococcus HLAR in dogs and cats poses a public health concern, as it increases the risk of environmental dissemination and has implications for One Health.